Engine-Pong/Shared/Behaviours/BallBehaviour.cs

using Syntriax.Engine.Core;
using Syntriax.Engine.Physics2D;

namespace Pong.Behaviours;

public class BallBehaviour : Behaviour2D
{
    public float Speed { get; set; } = 500f;
    public float SpeedUpMultiplier { get; set; } = .0125f;

    public IRigidBody2D rigidBody = null!;

    protected override void OnFirstActiveFrame()
    {
        BehaviourController.GetRequiredBehaviour<ICollider2D>().OnCollisionDetected += OnCollisionDetected;
        rigidBody = BehaviourController.GetRequiredBehaviour<IRigidBody2D>();
    }

    public void LaunchBall(Vector2D launchDirection)
    {
        rigidBody.Velocity = launchDirection * Speed;
    }

    public void ResetBall()
    {
        Transform.Position = Vector2D.Zero;
        rigidBody.Velocity = Vector2D.Zero;
    }

    protected override void OnUpdate()
    {
        if (rigidBody.Velocity.MagnitudeSquared <= 0.01f)
            return;

        Vector2D speedUp = rigidBody.Velocity.Normalized * Universe.Time.DeltaTime;
        rigidBody.Velocity += speedUp * SpeedUpMultiplier;
    }

    private void OnCollisionDetected(ICollider2D collider2D, CollisionDetectionInformation information)
    {
        if (Math.Abs(information.Normal.Dot(Vector2D.Right)) > .25)
            rigidBody.Velocity = information.Detected.Transform.Position.FromTo(information.Detector.Transform.Position).Normalized * rigidBody.Velocity.Magnitude;
        else
            rigidBody.Velocity = rigidBody.Velocity.Reflect(information.Normal);
    }

    public BallBehaviour() { }
    public BallBehaviour(float speed) => Speed = speed;
}